Device for the treatment of ferrous metal ingots which are intended to be removed from molds without hold-up periods

ABSTRACT

The device is constituted by a heat-insulating and/or exothermic lining, comprising a single element or a number of juxtaposed elements, provided with a metallic reinforcement which has an extensive open structure and forms meshes. One portion of the meshes is embedded in the thickness of the lining, whilst another portion, adjacent to the volume which is filled with molten metal, is uncovered. Since the contact surfaces between the mold and the metallic portions which serve to clamp the lining to the mold are quite small, the transmission of heat from the metal to the upper portion of the mold is greatly reduced with respect to known devices. Moreover the manufacture of each element only requires placing the corresponding portion of the reinforcement in a mold with permeable walls, wherein a slurry is fed; and the bonds between the lining, the reinforcement and the ingot are improved, which allows early displacement of the ingot after its removal from the mold.

[ Jan. 15, 1974 10/1962 France................................ 249/20178,287 5/1962 276,166 10/1964 Nether1ands..... ,309,266

[57] ABSTRACT DEVICE FOR THE TREATMENT OF FERROUS METAL INGOTS WHICH AREINTENDED TO BE REMOVED FROM 1 MOLDS WITHOUT HOLD-UP PERIODS PrimaryExaminerJ. Spencer Overholser [76] Inventors: Andre Daussan; JeanCharles Daussan; Gerard Daussan, all of 9, 2321 ggg gy i ffi :s AvenueLeclerc de l-lauteclocque, neyg p n Metz, France Sept. 27, 1971 [21]App]. No.: 183,767 The device is constituted by a heat-insulating and/orexothermic lining, comprising a single element or a Foreign Applicationpriority Data number of juxtaposed elements, provided with a me- Oct 71970 France 7036202 tallic reinforcement which has an extensive openstructure and forms meshes. One portion of the U S Cl 249/197 164M249/199 meshes is embedded in the thickness of the lining, 111' Bzzd7/10 whilst another portion, adjacent to the volume which Fieid isfilled with molten metal, is uncovered. Since the 249 200 contactsurfaces between the mold and the metallic portions which serve to clampthe lining to the mold References Cited are quite small, thetransmission of heat from the metal to the upper portion of the mold isgreatly re- UNITED STATES PATENTS duced with respect to known devices.Moreover the United States Patent Daussan et a1.

[22] Filed:

manufacture of each element only requires placing the correspondingportion of the reinforcement in a mold with permeable walls, wherein aslurry is fed; and the bonds between the lining, the reinforcement andthe ingot are improved, which allows early displacement of the ingotafter its removal from the mold.

3,106,756 Demaison.......... 3,165,797 LaBate............... 3,561,722Kobusch et 211.... 3,512,572 Ednell................ 1,815,186Co1es......,.......... 2,663,920

164/57 4 Claims, 33 Drawing Figures Anthony...........,.......

FOREIGN PATENTS OR APPLICATIONS 906,478 9/1962 GreatBritain........................

PATENTEDJAH 1 5 1974 saw 01 or 10 PATENTEUJAN I 51174 SHEET 0%. 0F 10Fig.7? 41 Fig.73

PATENTEUJAN 1 5 I974 SHEET us nr 10 Fig. 77

a ig Fig/.78

SHEET 01 or 10 PATENTEU JAN 1 51974 PATENTEUJAN 1 51914 3. 785 609 SHEET08 0F 10 Fig.27 4

PATENTEBJAN 1 51374 sum as or 1o DEVICE FOR THE TREATMENT OF FERROUSMETAL INGOTS WHICH ARE INTENDED TO BE REMOVED FROM MOLDS WITHOUT HOLD-UPPERIODS This invention relates to the pouring of ferrous metals intomolds such as ingot-molds or raised top sections of ingot-molds and ismore particularly directed to a device for the treatment offerrous-metal ingots which are intended to be removed from molds withouthold-up periods.

It is known to place over the internal surface of an ingot-mold eitherin the upper portion of this latter or within the interior of a raisedtop section a heatinsulating and/or exothermic lining which is intendedto maintain liquid metal at the top portion of the bath during thesolidification process for a sufficiently long period of time to ensurethat the shrinkage cavities of the ingot are filled with the metal whichhas remained in the liquid state.

It is also known to complete the action of the abovementioned laterallining by means of a heat-insulating and/or exothermic powder orso-called covering powder which is spread over the surface of the moltenmetal bath during filling of the ingot-mold or immediately afterwards.

The conventional hold-up period during which ingotmolds remainstationary after filling in order to demold ingots and displace theselatter without danger varies respectively and broadly speaking betweenninety minutes and five or six hours in the case of ingots of 5 to tons.This results in high costs not only in regard to immobilization ofingot-molds but also as a result of re tention in pit-type heatingfurnaces the foregoing indications are dependent on a number of factorsand can be given only in order to give a clear idea.

Whatever precautions are taken in the pouring of ingots, theabove-mentioned hold-up of ingot-molds cannot be substantially reducedwithout thereby impairing the quality of the ingot or like casting andwithout increasing the dangers involving personnel employed inoperations of demolding and removal from the area which is used forfilling ingot-molds.

In order to reduce the hold-up time, a known type of ingot-mold liningalready exists (as disclosed in French Pat. No. 1,548,778) and is madeup of heat-insulating plates which are reinforced on that face which isdirected towards the ingot-mold wall. The reinforcement extends beyondthe bottom edges of the plates and/or is fixed on the plates by means ofmetal studs which pass through said plates and project from the facewhich is directed towards the interior of the ingotmold. The moltenmetal which rises within the ingotmold is welded to those portions ofthe reinforcement which are not covered by the heat-insulating plates,said plates being thus attached to the ingot once this latter hassolidified at its periphery. The ingot can then be removed from the moldand displaced without incurring the dangers mentioned above.

However, the use of a reinforced lining of this type results in asubstantial heat loss through the reinforcement which is in contact withthe ingot-mold wall over a large area. Furthermore, this type of liningis relatively complicated and costly to manufacture.

The present invention is intended to overcome these disadvantages whileobtaining better behavior of the ingots or like castings duringsolidification in order to reduce losses of metal.

In accordance with the invention, the device for the treatment offerrous-metal ingots which are intended to be demolded very shortlyafter filling of molds such as ingot-molds or raised top sections ofingot-molds is constituted by a heat-insulating and/or exothermic liningcomprising a single element or a number of juxtaposed elements removablyfixed prior to pouring and adjustable for height within the upperportion of the ingot-mold and in contact with the internal wall of saidmold, said lining being provided with a metallic reinforcement which iswelded to the molten metal when said metal is poured into the mold sothat the lining is thus maintained in contact with the ingot until saidingot is introduced into the rolling mill. The device is distinguishedby the fact that the metallic reinforcement has an extensive openstructure and forms meshes of which one portion is embedded in thethickness of the lining whilst anothe portion is uncovered, theuncovered portion being adjacent to the volume which is filled withmolten metal during the pouring operation.

By means of this device, the transmission of heat from the molten metalof the metal which is in process of solidification to the upper portionof the mold is much lower than in the case of devices which have beenknown up to the present time since the contact surfaces between the moldand the metallic portions which serve to clamp the lining are very smallor even wholly absent.

Moreover, the manufacture of each element of the lining is simple andeconomical since it is only necessary to place the corresponding portionof the reinforcement in a mold having permeable walls and a slurrycontaining in suspension the heat-insulating and- /or exothermicsubstance which is intended to constitute the lining is fed into theinterior of said mold.

Finally, the bond which is formed on the one hand between thereinforcement and the heat-insulating and- /or exothermic substance ofthe lining and on the other hand between said reinforcement and theingot during solidification is very appreciably enhanced by virtue ofthe fact that the reinforcement is provided with open portions and formsmeshes it is therefore possible to displace the ingot immediately afterremoval from the mold and with the minimum danger.

By virtue of the invention, the yield of the metallurgical operationconsidered has been successfully increased from 86 to 92 this yieldrepresents the weight of the sound ingot which is freed from the topcrop-end, from the bottom crop-end and from surface oxidations asrelated to the weight of the as-cast ingot. Since the second and thethird causes of losses remain the same, the resulting improvement in theyield which is solely due to a reduction in the top crop-end can attainapproximately 6 this improvement is considerable since the smallest topcrop-end which was obtained in the prior art was ll The lining inaccordance with the invention is preferably provided with recesses whichuncover part of the meshes of the reinforcement and communicate with themolten metal through at least one lateral opening at the latest whensaid metal reaches its highest level within the mold.

In an advantageous embodiment of the invention, provision is made forthe addition of a device for distributing covering powder the devicewhich is employed as a lining automatically forms a cover which has acentral opening and is intended to facilitate demolding of the ingot andtransportation of this latter to the pit-type furnace or to any otherlocation in order to ensure that the area such as the casting pit atwhich the filling of ingot-molds takes place is cleared in a very shortperiod of time.

Further advantages and characteristic features of the invention willbecome apparent from the following description.

Different embodiments of the invention are illustrated in theaccompanying drawings which are given solely by way of non-limitativeexample, and in which FIG. 1 is a vertical half-sectional view takenalong line I-I of FIG. 3, in which the device and the top portion of theingot-mold are shown prior to pouring in a first embodiment of theinvention FIG. 2 is a vertical half-sectional view taken along lineII-II of FIG. 3, in which the device and the top portion of theingot-mold are shown at the end of filling with molten metal FIG. 3 is acorresponding horizontal sectional view taken along line III-III of FIG.I and prior to pouring FIG. 4 is a plan view in actual size and showinga fragment of metallic reinforcement of a particular type FIG. 5 is avertical sectional view taken along line VV of FIG. 6 and showing asecond embodiment of the invention FIG. 6 is the correspondinghorizontal sectional view taken along line VIVI of FIG. 5

FIG. 7 represents a half-elevation of one of the elements whichconstitutes the device in a third embodiment of the invention FIG. 8 isa vertical sectional view taken along line VIIIVIII of FIG. 7

FIG. 9 is a half-view in plan corresponding to FIG. 7

FIG. 10 is a diagrammatic cutaway view in perspective showing one of theelements constituting the device in an alternative form of the thirdembodiment of the invention FIG. 11 is a half-view in elevation showingone of the elements constituting the device in a fourth embodiment ofthe invention FIG. 12 is a vertical sectional view taken along lineXIIXII of FIG. 11

FIG. 13 is a horizontal half-sectional view taken along line XIIIXIII ofFIG. 11

FIG. 14 is a perspective view of the element which is illustrated inFIGS. 11, 12 and 13, this view being taken on the side opposite to thatwhich is visible in FIG. 11

FIG. 15 is a view which is similar to FIG. 14 but relates to analternative form of the fourth embodiment of the invention FIG. 16 is aview in elevation showing one of the elements constituting the device ina fifth embodiment of the invention FIG. 17 is a vertical sectional viewtaken along line XVII-XVII of FIG. 16

FIG. 18 is a horizontal sectional view taken along line XVIII-XVIII ofFIG. 16

FIG. 19 is a perspective view of an element which forms part of analternative form of the fifth embodiment of the invention FIG. 20 is avertical sectional view taken along line XX-XX of FIG. 21 and showingthe top portion of an ingot-mold fitted with a device corresponding to asixth embodiment of the invention FIG. 21 is a horizontal sectional viewtaken along line XXL-XXI of FIG. 20

FIG. 22 is a horizontal sectional view taken along line XXIL-XXII ofFIG. 23

FIG. 23 is a view in elevation showing two consecutive elements of thedevice illustrated in FIGS. 20 and 21, said elements being opened-outalong a common vertical plane FIG. 24 is a view in elevation showing oneof the two clamping wedges forming part of the device which isillustrated in FIGS. 20 and 21 FIG. 25 is a vertical sectional viewtaken along line XXVXXV of FIG. 26 and showing the top portion of aningot-mold which is fitted with a device corresponding to a seventhembodiment of the invention FIG. 26 is a plan view corresponding to FIG.25

FIG. 27 is a vertical sectional view taken along line XXVII-XXVII ofFIG. 28 and showing the top portion of an ingot-mold which is fittedwith a device corresponding to an eighth embodiment of the inventionafter filling with molten metal and incipient solidification of thislatter FIG. 28 is a plan view corresponding to FIG. 27, assuming thatthe hopper which is placed above the device has been removed FIG. 29 isa vertical half-sectional view taken along the chain-dotted lineXXIXXXIX of FIG. 31 and showing the top portion of an ingot-mold fittedwith a device corresponding to a ninth embodiment of the invention priorto pouring of the metal FIG. 30 is a vertical half-sectional view takenalong the chain-dotted line XXXXXX of FIG. 31 and showing the topportion of an ingot-mold fitted with a device corresoponding to a ninthembodiment of the invention after filling with metal and incipientsolidification of this latter FIG. 31 is a plan view corresponding toFIGS. 29 and 30 FIG. 32 is a fragmentary perspective view showing one ofthe elements constituting the device in accordance with the secondembodiment of the invention and looking on that side which is in contactwith the mold FIG. 33 is a view which is similar to FIG. 32 but relatesto an alternative form of the second embodiment of the invention.

There is shown in FIGS. 1 to 3 the top portion of an ingot-mold 1 withinwhich is placed a lining 11 formed in known manner by four plates 12 andfour clamping wedges 13 the horizontal cross-section of these latterprogressively decreases in the downward direction but the reversearrangement could also be adopted, in which case the clamping action isproduced by the plates instead of the wedges.

In accordance with the invention, a metallic reinforcement 14 isembedded in each of the plates 12 and in each of the wedges 13. Oneexample of construction of said metallic reinforcement 14 is given inFIG. 4 which shows a wire-netting reinforcement in actual size. However,many other designs are possible without departing from the scope of theinvention. A first set of designs comprises substantially linearmetallic elements in intercrossed relation which may or may not bejoined together these elements can be wires but also suitably orientedmetal rods or expanded" metal. A second set of designs of thereinforcement comprises perforated metal sheets and these latter can inparticular be either flat, corrugated or even provided with pleats.

There would still be no departure from the scope of the invention ifprovision were made for metallic reinforcements only within the plates12 but not in the wedges 13 or if the metallic reinforcement 14 of oneplate 12 were made up of a number of sections separated from each other.

That portion of the lining 11 which is located between the metallicreinforcement 14 and the internal wall of the ingot-mold 1 is providedwith recesses consisting of substantially vertical channels 15 whichopen at the top into the atmosphere and are closed at the lower ends.Further recesses are constituted by lateral openings 16 each providing acommunication between the base of each channel 15 and the internal faceof the lining 11 which is in contact with the molten metal 2 during thepouring operation.

When the level of the molten metal rises within the ingot-mold 1, saidmetal comes into contact with the metallic reinforcement 14 through thelateral openings 16, then fills the channels 15 along which said moltenmetal is also in contact with the metallic reinforcement 14 as shown inFIG. 2. When the poured metal solidifies, said metal is welded to themetallic reinforcement 14 at the bottom of the lateral openings 16 andthe channels 15. Once the solidification is sufficiently far advanced,the lining 11 is surrounded by thin metal lugs formed within thechannels 15 said lugs are welded to the metallic reinforcement which isin turn welded to the mass of the ingot by the metal which fills thelateral openings 16. If the reinforcement has sufficient strength, thelining cannot be separated from the ingot when this latter is removedfrom the mold and then transported into the pittype heating furnacesthis separation takes place only at the moment rolling when the ingot isflattened by the rolls of the rolling-mill.

In this embodiment, the air which is forced back by the molten metal asthis latter penetrates into the lateral openings 16 and into thechannels 15 as well as the gases which are given off by the molten metalare discharged to the surrounding atmosphere through the open upperextremities of the channels 15.

For the correct performance of operations, it is naturally essential toensure that the metal forming the reinforcement 14 is welded to themetal 2 which is poured into the ingot-mold when these two metals are incontact with the lower ends of the recesses formed in the lining 11 itis also essential to ensure that the metal of the reinforcement 14retains appreciable mechanical strength at the temperatures to whichsaid reinforcementis heated between pouring and rolling.

Said reinforcement can advantageously be formed by means of a gridhaving hexagonal meshes as standardized in Germany under the designationDrahtgitter No. 9 D-l DIN l7l40 and the analysis of which complies withthe following conditions carbon less than 0.10

manganese less than 0.50

phosphorus less than 0.09

sulphur less than 0.08

In a second embodiment of the invention which is illustrated in FIGS. 5,6 and 32, the metallic reinforcement 24 of each of the plates 22 whichform the lining 21 when assembled together is provided with a series ofvertical pleats this series defines alternately salient and re-entrantvertical bands so that the cross-section of the reinforcement along ahorizontal plane forms a so-called box-pleat pattern. The salientvertical bands 28 of the reinforcement 24 are located on the externalsurface of the lining 21 which is in contact with the ingot-mold 1 atthe moment of positioning for pouring. The reentrant bands 29 areembedded in the plates 22, with the result that the metallicreinforcement 24 is firmly anchored in the lining 21.

In this second embodiment, the lining 21 is provided as in the firstembodiment with recesses consisting of vertical channels 25 and lateralopenings 26. The vertical channels 25 are again formed in that face ofthe lining 21 which is in contact with the ingot-mold 1 however, insteadof being located outside the reinforcement with respect to the pouredmetal, said channels are separated from the ingot-mold l by the salientvertical bands 28 furthermore, said channels are usually open at bothends, namely to the surrounding atmosphere at the top and to the pouredmetal at the bottom. The lateral openings 26 extend directly to thebottom of the vertical channels 25 without interposition of any portionof reinforcemennt.

During the pouring operation, the result achieved is exactly the same asin the case of the device according to the first embodiment of theinvention except for the fact that the molten metal first penetratesinto the channels 25 at the lower ends thereof before passing throughthe lateral openings 26 after solidification of the poured metal, themetal lugs are directly welded to the ingot at the lower ends thereof.

In a first alternative form of this second embodiment of the inventionwhich is illustrated in the central portion of FIG; 5 and in theright-hand portion of FIG. 32, the vertical channels 27 do notcommunicate with the atmosphere through the upper ends thereof but eachchannel stops at the level of the lateral opening 26 and is incommunication with this latter. The lower end of the correspoding metallug is welded to the ingot but this lug is not formed up to the fullheight of the lining 21 it can nevertheless attain three-quarters ofthis height or even slightly more.

In a second alternative embodiment, the lining is not provided with alateral opening and the vertical channels 27 shown in FIG. 33 terminatein a blind end at the top. In this case, the molten metal which riseswithin the channels compresses the air which is imprisoned therein andstops before having reached the ends of the channels; it is furtherobserved in some instances that the metal remains in the liquid stateover a longer period of time within the channels, thereby endowing themetal lugs with higher strength.

A number of different alternative designs may clearly be combined withinthe same lining as is the case with the lining shown in FIG. 5.

It can also be noted from FIGS. 5 and 6 that the lining 21 which isillustrated is constituted solely by four plates 22 having juxtaposededges which are inclined to the faces at an angle of 45 however, it isreadily understood that this lining could also be provided with clampingwedges similar to those shown in FIGS. 1, 2 and 3.

According to a third embodiment of the invention which is illustrated inFIGS. 7, 8 and 9, the recesses formed in the plates 32 which constitutethe lining 31 are provided with lateral openings 36 similar to those ofthe two first embodiments and with vertical passages 35 which are whollyformed within the interior of each plate 32. The lateral openings 36extend into the vertical passages 35 which communicate with theatmosphere at the upper ends thereof but stop at the lower ends at thelevel of those lateral openings 36 which are located nearest the bottomof the plate 32.

The metallic reinforcement 34 is placed within the plate 32 in such amanner as to ensure that the vertical passages 35 are adjacent theretoand that said reinforcement is located on the side remote from thelateral openings 36 with respect to said passages.

In this case, the metal lugs which are formed within the verticalpassages 35 during solidification are isolated from the ingot-mold bypart of the thickness of the lining 31, thereby reducing heat losses.

In accordance with an alternative form of this third embodiment of theinvention as illustrated in FIG. 10, the metallic reinforcement 34 islocated on the same side as the lateral openings 36 with respect to thevertical passages 37. In consequence, the metal lugs which are formed asa result of solidification of the metal are located externally of thereinforcement with respect to the ingot.

In a fourth embodiment of the invention which is illustrated in FIGS.11, l2, l3 and 14, the recesses formed in each plate 42 whichconstitutes the lining 41 are provided with lateral openings 46 whichare similar to those of the three first embodiments and with verticalchannels 45 formed in that face of the plate 42 which is in contact withthe ingot-mold at the moment of pouring. However, said vertical channels45 have a horizontal cross-section which is insufficient to permit themolten metal to pass into the channels by reason of its high viscosityin addition, the channels do not communicate directly with the lateralopenings 46 but by means of horizontal ducts 48 of small cross-sectionalarea.

The metallic reinforcement 44 is completely embedded in the plate 42except at the bottom of each lateral opening 46, at which thereinforcement is uncovered over an area which is equal to the verticalcross-section of said opening.

During the pouring operation, the molten metal fills the lateralopenings 46 and is welded to the metallic reinforcement 44 at the bottomof said openings. The horizontal ducts 48 and the vertical channels 45permit the discharge of air and of the gases which are given off by themolten metal. After solidification, the lining 41 is retained againstthe ingot only by the metallic reinforcement 44 which is in turnattached to the ingot by means of a small number of welds.

In an alternative form of this fourth embodiment of the invention asshown in FIG. 15, the lining is provided instead of the verticalchannels 45 with vertical ducts 47 having a small cross-sectional areaand entirely formed within each plate 42, the upper ends of said ductsbeing intended to communicate with the atmosphere and the lower endsbeing intended to communicate with the horizontal ducts 48 of smallcrosssectional area.

In a fifth embodiment of the invention which is illustrated in FIGS. l6,l7 and 18, each plate 52 in the assembly of plates which constitutes thelining 51 is provided at one end with an extension forming a return 53so that the horizontal cross-section of the plate has the shape of aright-angle in addition, the end faces of each plate 52 are inclined tothe vertical, the complete lining 51 being consequently jammed inposition when assembled in the ingot-mold l.

The recesses of the lining consist solely of lateral openings 56 formedin that face of the lining which is in contact with the molten metal atthe moment of pouring. These lateral openings 56 have a flared shape,the largest cross-section being located at the end nearest the moltenmetal bath said shape can be that of a frustum either of a pyramid or ofa cone having a horizontal axis.

The metallic reinforcement 54 is completely embedded in the plate 52except at the bottom of each flared lateral opening 56 where saidreinforcement is uncovered over an area equal to the smallest verticalcrosssection of said opening. The reinforcement consists of a series ofvertical pleats forming a box-pleat pattern in horizontal cross-sectionand is therefore made up of salient bands 58 and re-entrant bands 59,the flared openings 56 being adjacent to the bands last mentioned. Thisarrangement of the metallic reinforcement 54 results in a greaterthickness of the plates 52 and endows the lining 51 with added strength.Finally, the metallic reinforcement 54 is provided with a right-angledreturn 55 in the same manner as the plate 52 in which said reinforcementis embedded.

At the time of pouring and when the molten metal penetrates into one ofthe flared lateral openings 56, the air and the gases which are givenoff by the metal are discharged along the upper portion of said openingby virtue of the fact that this latter is inclined to the horizontal.The molten metal can thus be welded to the metallic reinforcement 54 atthe bottom of each flared lateral opening and no other recess isnecessary.

In an alternative form of this fifth embodiment of the invention asshown in FIG. 19, the metallic reinforcement 54 is flat but is providedwith a right-angled extension 55 as in FIG. 18.

In a sixth embodiment of the invention which is illustrated in FIGS. 20,21, 22, 23, 24, the lining 61 is an articulated lining constituted byfour plates 62 and by two wedges 63, the plates 62 being such as to formtwo pairs which are separated from each other by the wedges 63. Eachplate 62 and each wedge 63 is provided on that face which is in contactwith the molten metal at the moment of pouring with flared lateralopenings 66 which are similar to the openings 56 described earlier. Eachpair of plates has a flat metallic reinforcement 64 which is common tothe two plates said plates are thus secured to each other while beingcapable of pivotal movement with respect to each other about a hinge 65constituted by the vertical section of the metallic reinforcement 64which is located at the end of the two plates.

It is apparent from FIGS. 21 and 22 that the metallic reinforcement 64is completely embedded in the pair of plates 62 with which thereinforcement is associated except at the bottom of each flared lateralopening 66 and along the hinge 65. However, the use of articulatedplates which is a distinctive feature of the sixth embodiment of theinvention is not limited in any sense to the mode of connection betweenthe metallic reinforcement of the lining and the poured metal which isshown in FIGS. 20 and 21. Similarly, the use of wedges 63 does notconstitute an essential requirement of this embodiment.

Moreover, the metallic reinforcement could be common to more than twoplates and serve, for example, as a connecting element between all theplates of a single lining of the type shown in FIG. 6.

In a seventh embodiment of the invention which is illustrated in FIGS.and 26, the lining 71 is made up of four plates 72 having juxtaposededges which are inclined to the faces at an angle of 45 and are notprovided with any recess. The metallic reinforcement 74 of each plate 72has a series of horizontal pleats located substantially at right anglesand forming a box-pleat pattern in vertical cross-section thereinforcement is therefore made up of salient bands 78 and re-entrantbands 79. The salient bands 78 are applied against that face of theplate 72 which is in contact with the molten metal during the pouringoperation whereas the reentrant bands 79 are embedded in the plate. Whenthe molten metal fills the ingot-mold, it is welded to the salient bands78 and the lining is thus retained against the ingot until this latteris subjected to a rolling operation.

This particularly simple mode of connection between the lining and theingot can also be carried out with vertical bands which are alternatelysalient and reentrant or even with bands which are oriented in anymanner with respect to the axis of the ingot-mold. It would also bepossible to make use of metallic reinforcement with salient portionswhich are welded to the molten metal and re-entrant portions which areembedded in the lining but the salient and re-entrant portions need notnecessarily have a configuration of bands arranged uniformly inalternate succession.

In an eighth embodiment of the invention which is illustrated in FIGS.27 and 28, the lining 81 is made up of four plates 82, the top portionsof which are bentback towards the interior of the mold l. The assemblyconsisting of inwardly bent portions 83 of the plates 82 forms a virtualcover for the molten metal bath and this cover is provided with'acentral opening 89. The metallic reinforcement 84 of each plate 82 isprovided at the top with an inwardly bent portion 87 which closelycorresponds in shape to the corresponding portion 83 of the plate.

The lower portion of the lining 81 which is in contact with the wall ofthe ingot-mold 1 has the arrangement which is described above inconnection with the fourth embodiment of the invention and illustratedin FIGS. 11 to 14. Thus, each plate 82 is provided with lateral openings86 at the bottom of which the molten metal is welded to the metallicreinforcement 84 and with vertical channels 85 having a smallcross-sectional area for the discharge of air and gases, the lateralopenings 86 being intended to communicate with the vertical channels 85by means of narrow ducts 88. However, arrangements which are differentfrom this latter and arise from other embodiments of the invention asdescribed in the foregoing could also be adopted for the lower portionof the lining 81.

The inwardly bent portion 83 of each plate 82 has bottom openings 91which are similar to the lateral openings 86 and at the bottom of whichthe molten metal is welded to the inwardly bent portion 87 of themetallic reinforcement vertical ducts 92 of small cross-sectional areaprovide a communication between the ends of the bottom openings 91 andthe surrounding atmosphere for the purpose of discharging air and gases.

A hopper 4 is placed above the central opening 89 of the lining 81 andis applied against the top edges of the inwardly bent portions 83. Thehopper can be filled with an insulating and/or exothermic coveringpowder 5 in order to supply the shrinkage cavity 3 of the mo]- ten metalbath which is formed during solidification of the molten metal 2. At theend of the shrinkage process, a solidified metal film continues toadhere to the underface of the inwardly-bent portions 83 of the lining81 and the strength of this latter is thus increased.

In FIG. 28, it is assumed that the hopper 4 has been removed.

In an alternative form of this eighth embodiment of the invention asshown in FIGS. 29, 30 and 31, the inwardly-bent portion 83 of each plate82 has inclined passages 93 which open at the top ends in the edge ofthe central opening 89 and which are provided with downward extensionsin the form of vertical ducts 94 in that portion of the lining which isin contact with the ingot-mold. The said ducts communicate with openings96 formed in those faces of the plates 82 which are in contact withthe-molten metal and may extend to the base of the lining 81 ifnecessary. Vertical ducts 92 and vertical channels which are both ofsmall crosssectional area establish a communication between the inclinedpassages 93 and the lower portion of the vertical ducts 94 respectivelyand the surrounding atmosphere.

The metallic reinforcement 84 and the inwardly bent portion 87 whichforms an upward extension of said reinforcement are adjacentrespectively to the vertical passages 94 and inclined passages 93. Yaidpassages are filled during the pouring operation with molten metal whichcan penetrate therein either through the lower ends which communicatewith the openings 96 or through the upper ends which'open in the edge ofthe central opening 89 the air and the gases are discharged to theatmosphere through vertical ducts 92 and through the vertical channels85. The metal which has filled the passages is welded to the metallicreinforcement 84 and to the inwardly bent portion 87, thus ensuring avery effective connection between the ingot and the lining and at thesame time increasing the cohesion between that portion of each plate 82which is in contact with the internal wall of the mold l and theinwardly bent portion 83 which forms part of the cover.

In FIG. 29, there are shown the openings 96 having a flared shape asdescribed in the fifth embodiment of the invention and the openings ofthe bottom row which do not communicate with the vertical channels 85.It is apparent that many combinations can be obtained between the formof lining comprising a cover which is illustrated in FIGS. 27 to 31 andthe different modes of connection between the metallic reinforcement andthe lining which are illustrated in the preceding figures.

In all the embodiments of the invention which have been described in theforegoing, the lining can be constituted by an insulating and/orexothermic material, the following analyses of which are given only byway of example and without any limitation.

Insulating material Formula I fl 5 nq oneness index: 70) to Mineral ororganic binder 5 to 10 Formula II Fibrous refractory materials such asasbestos or rock wool l to 35 Fibrous organic materials such as sawdustor paper pulp l to 20 7n Refractory or semi-refractory mineral materialssuch as silica. magnesia or diatomaceous earth 45 to /1 Natural orsynthetic. mineral or organic binder l to l5 Exothermic materialOxidants 20 to 5 Aluminum 8 to 30 71 Fibrous refractory materials(asbestos or rock wool, for example) 1 to 35 Fibrous organic materials(paper pulp sawdust, etc) 1 to 20 71 More or less refractory mineralmaterials such as silica, magnesia, diatomaceous earth, etc. 45 to 90 7:Binder (mineral or organic, natural or synthetic starchy materials.phenolic resin,

sodium silicate) l to 7c The insulating and/0r exothermic coveringpowder 5 which was mentioned in connection with the eighth embodimentcan correspond to one of the following analyses which are also given byway of non-limitative example.

Insulating covering powder Alumina 30 to 40 7c Silica 40 to 30 Carbon 10to Fluxes such as sodium carbonate l0 to 5 "/1. Fluorspar l0 to 5 '7:

Exothermic covering powder Silica or alumina 44 to 67 Carbon 20 to 5Fluorspar l to 5 74 Aluminum to 8 Oxidants 5 to 15 71.

Generally speaking, the invention is obviously not limited to theembodiments which have been described and many alternative forms otherthan those which were mentioned in the foregoing description canaccordingly be contemplated. In particular, the lining could be designedin a single-unit form such as a pot or cup without departing from thescope of the invention.

The metallic reinforcement can extend to the full height of the liningas is illustrated in particular in FIG. 5 or only to a part of thisheight as is shown in the majority of the figures. The height of themetallic reinforcement is preferably within the range of 30 to of theheight of the lining. When the metallic reinforcement only extends to apart of the height of the lining, the top edge of the reinforcement ispreferably located in the vicinity of the top edge of the lining sinceit is the top portion of this latter which can most usefully bereinforced and securely attached to the ingot.

We claim:

1. A lining for retarding cooling of ferrous-metal ingots which areintended to be demolded very shortly after filling of molds such asingot-molds or raised top sections of ingot-molds, said lining beingremovably fixed prior to pouring and adjustable for height within theupper portion of the ingot-mold and in contact with the internal wall ofsaid mold, the body of said lining having its outer surface shaped tocontact the inner wall ofa mold about the upper portion of the mold andhaving embedded therein a metallic reinforcement which is to be foundedto the molten metal when said metal is poured into the mold wherein thesaid metallic reinforcement has an extensive open structure and formsmeshes, and wherein the lining has a plurality of spaced, inwardlyopening recesses which extend from the inner surface of the lining to adepth sufficient to uncover a part of the meshes of the reinforcementonly at spaced points on the reinforcement without creating a completediscontinuity in the body of the lining material.

2. A lining as claimed in claim 1, said recesses having a flared shapethe largest cross section of which is located on the internal face ofthe lining with which the molten metal comes into contact during thepouring operation.

3. A lining as claimed in claim 1, said lining spacing and insulatingsaid metal reinforcement from said internal wall of said mold.

4. A lining as claimed in claim 3, said reinforcement being entirely outof contact with said internal wall of said mold.

1. A lining for retarding cooling of ferrous-metal ingots which areintended to be demolded very shortly after filling of molds such asingot-molds or raised top sections of ingot-molds, said lining beingremovably fixed prior to pouring and adjustable for height within theupper portion of the ingot-mold and in contact with the internal wall ofsaid mold, the body of said lining having its outer surface shaped tocontact the inner wall of a mold about the upper portion of the mold andhaving embedded therein a metallic reinforcement which is to be boundedto the molten metal when said metal is poured into the mold wherein thesaid metallic reinforcement has an extensive open structure and formsmeshes, and wherein the lining has a plurality of spaced, inwardlyopening recesses which extend from the inner surface of the lining to adepth sufficient to uncover a part of the meshes of the reinforcementonly at spaced points on the reinforcement without creating a completediscontinuity in the body of the lining material.
 2. A lining as claimedin claim 1, said recesses having a flared shape the largest crosssection of which is located on the internal face of the lining withwhich the molten metal comes into contact during the pouring operation.3. A lining as claimed in claim 1, said lining spacing and insulatingsaid metal reinforcement from said internal wall of said mold.
 4. Alining as claimed in claim 3, said reinforcement being entirely out ofcontact with said internal wall of said mold.